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Particulate matter arising from usual activities in urban area is generally indicated as dangerous pollutant. We are reporting some data obtained by aerosol spectrometer which allowed us to know the concentration of three classes of particulate matter (PM10, PM2,5, PM1). The comparison of data recorded in summer and in winter and in some days presenting a particular social situation or in particular weather conditions, indicates the possibility to discriminate the particulate matter amount arising from traffic and arising from other human activities, mainly from heating house. This possibility is due to the values of ratio of the amount of particulate matter: PM10/PM2,5 and PM10/PM1 ratio are near to 1 value for PM deriving from heating house and they are much higher for PM deriving from traffic. The tentative evaluation of the relative importance of the two main sources of particulate matter is about half for one, but the emission of particulate matter of heating house is largely predominant in the presence of some meteorological events such as thermal inversion. The fashion regarding heating house by firewood heaters, without any check or abatement, aggravates the hazards associated to the home heating. However, the pollution from traffic regards the whole year, while the pollution from heating house is on 5 or 6 months only. Consequently, the relative importance of the two sources in releasing PM10 in air in a year results in four times higher for traffic than for home heating.

Deuterium labelled compounds possess a wide range of applications in pharmaceuticals, environmental, materials and chemical sciences. They are useful in the investigation of bio-active molecules, giving detailed insights into the mechanism of chemical reactions. The deuteration of fatty acids, including stearic acid and its derivatives, permits to obtain reference or standard compounds for many purposes, including studies on metabolic pathways and analytical determinations. This paper refers to hydroxystearic acids, a class of compounds of interest in many applied fields focusing particular attention on the most used deuterium-labelling methodologies and related problems. An outline on the main applications of deuterated hydroxystearic acids is also done, critically discussing the examples taken from the literature. Furthermore, new results are presented concerning a simple protocol for obtaining D2 ‘in situ’: using the seeds of Dimorphoteca sinuata L. as natural precursor, and a lab-scale apparatus developed by us, we have verified the possibility to obtain deuterium-pluri-labelled 9-hydroxystearic acid.

The use of two neural networks techniques to model wire electrical discharge machining process (WEDM) is explored in this paper. Both the back-propagation (BPN) and General Regression Neural Networks (GRNN) are used to determine and compare the WEDM parameters with the features of the surface roughness. A comparison between the back-propagation and general regression neural networks in the modeling of the WEDM process is given. It is shown that both the back-propagation and general regression neural networks can model the WEDM process with reasonable accuracy. However, back propagation neural network has better learning ability for the wire electrical discharge machining process than the general regression neural network. Also, the back-propagation network has better generalization ability for the wire electrical discharge machining process than does the general regression neural network.

Trans-4-hydroxy-2-nonenal (HNE) is one of the major terminal products both of chemically induced and of endogenous peroxidation of n-6 unsaturated fatty acids, so that it is frequently used as an indicator of the oxidative stress 'in vivo'. HNE is considered to be not only a potent cytotoxic and genotoxic compound, as evidenced by 'in vitro' studies, but even, owing to his existence at low concentrations also in normal cells, a messenger for cell signalling in physiological conditions (1). In addition, it has been showed that the concentration of lipid peroxidation products is relatively lower in undifferentiated, highly proliferating tumor cells with respect to normal cells, and it has been hypothesized that such products may play an important role in the down-regulation of cell proliferation. The electrophilic nature of HNE explains its chemical reactivity towards thiols, aminogroups of aminoacids, proteins or DNA bases (2). Previously we showed that, after exogenous administration to a human osteosarcoma cell line, SaOS2, HNE nuclear concentration increases about threefold and that such an increase correlates with cytotoxic and cytostatic effects [3]. In this work we have developed a method to allow a good separation of the single HNE-protein adducts. The accurate quantification of such adducts provides a powerful tool for the identification of molecular targets which could mediate the aldehyde effects. The HNE-protein adducts were reduced with NaB[3H]H4 to stabilize them and allow their autoradiographic detection. The nuclear extracts were analyzed in SDS-PAGE; in the first step of analysis a 12,5 % gel and Tris-Glicine running buffer was used to obtain the separation of all proteins extracted. In the second step a 10% polyacrilamide gel was employed with MOPS and MES running buffers; each buffer produced a different migration pattern when used with the same gel. In particular we observed that to optimize the separation of proteins ranging from 21 kDa to 66 kDa it was best to use MOPS running buffer; on the other hand to resolve proteins ranging from 2.5 kDa to 36 kDa the MES running buffer was the most indicated. Finally the large molecular weight proteins (400 kDa to 55 kDa) were separated using 4-8% polyacrlamide gel with Tris Acetate SDS running buffer. After autoradiography, the bands corresponding to the protein-adducts were excised and their radioactivity was evaluated by beta-counting. The results show that the method presented here is able to separate HNE-protein adducts from distinct intracellular compartments and it could be an efficient preparatory procedure for identification of modified protein in mass spectrometry. In particular, besides nuclei, we focused on the evaluation of HNE content in mitochondria with the aim to characterize apoptotis induced by HNE in a cell line p53 and pRB mutated.